Previous work has shown that optical imaging can be used to visualize maps of ocular dominance, orientation, and retinotopic position in the striate cortex of living animals. More recently we have shown that these techniques can also be applied to infant macaque monkeys and that the resulting maps suggest several developmental events that had not been suspected previously, namely: 1) that striate cortex in neonatal animals may grow anisotropically, expanding perpendicular to the ocular dominance columns, 2) that this differential growth may account for anisotropic magnifications seen in adults, and 3) that patterns of orientation selectivity and ocular dominance may drift in relation to each other as young animals mature. In order to evaluate these possibilities we propose further experiments to monitor the development of ocular dominance, orientation selectivity and cortical magnification in identified regions of striate cortex between birth and 14 weeks of age. By following the development of these patterns in the same cortical regions these experiments should avoid problems with individual variation and thereby provide clearer insights into the development of functional organization in the visual cortex of neonatal primates. Funds are therefore requested to supplement ongoing studies of adult striate cortex, so that attempts can be made to extend optical imaging techniques to longitudinal studies in infants.